Morphometrics and carcass production of Nile crocodile (Crocodylus niloticus) under intensive production system

Abstract

The aim of this study was to determine the carcass production and obtain linear models for the estimation of live weight of Nile crocodile (Crocodylus niloticus), reared under intensive system. Three-year-old crocodiles destined for slaughter were restrained, stunned and thereafter, the spinal cord severed instantly. The live weight of each crocodile was measured and the corresponding morphometric measurements were taken. The measurements included: body length, height at withers, heart girth, loin/inguinal girth, head width, head length, length of hind quarter and hindquarter width. Upon slaughter of the crocodiles, the carcass weight was measured and the dressing percentage was calculated. Independent sample T tests were used to determine significant differences between male and female morphometric measurements and production. Linear and multiple linear regressions were used to obtain models, for estimation of live weight of Nile crocodile. IBM® SPSS® statistics 24 was used for the analysis. The study revealed males were larger than females. With linear regression analysis, the highest accuracy of live weight prediction at 76% was achieved using heart girth. With multiple linear regressions, 85% accuracy in estimation of Nile crocodile live weight, under intensive system of production was achieved using all eight predictors. Key words: Body measurements, carcass, Crocodylus niloticus, linear models, live weight prediction.